In the construction and repair of concrete bridge decks, it is common to position a plurality of corrugated sheet steel panels in an overlapping manner on steel support beams for the deck to provide a permanent base form, and the panels may have various corrugated cross-sectional configurations. A wood or steel form is installed around the periphera of the assembled deck panels, and the steel peripheral forms may be attached to the steel deck panels to remain as permanent forms with the deck panels. Upper and lower layers or grids of reinforced steel rods or rebars are positioned at predetermined levels above the steel deck panels, and concrete is poured onto the deck panels up to the top level of the peripheral forms.
The problem of corrosion of the steel deck panels and the steel reinforcing rods or rebars within the concrete over a period of years is well known. Such corrosion is caused by atmospheric pollutants, road salt, vehicle emissions, acid rain and other pollutants. Over a period of years, the concrete decks deteriorate due to water seeping through pores and cracks within the concrete and contacting the steel reinforcement rods, causing them to corrode. Eventually, the support strength of the steel and concrete deck significantly reduces, thus requiring either reconstruction or replacement of the bridge deck. In order to avoid corrosion of the corrugated steel deck panels, it is known to use precast concrete panels which have embedded reinforcement, for example, as disclosed in U.S. Pat. No. 5,425,152. The precast concrete deck panels may also form parallel spaced concrete beams which may be prestressed or post-tensioned with reinforcing cables.
The present invention is directed to an improved composite deck system which is ideally suited for use in constructing bridge decks, and to the method of constructing the deck system. The deck system of the invention provides excellent corrosion resistance and thereby significantly increases the service life of bridge decks. The composite deck system also provides a cost effective or relatively inexpensive solution to forming a non-corrosive deck which is capable of supporting a substantial load over a long period of time. The deck system of the invention further enables the use of established design values for composite reinforcing materials in concrete so that bridge decks of various sizes and characteristics may be designed using conventional methods for designing bridge decks.
In accordance with a preferred embodiment of the invention, elongated composite deck sections or panels are formed by pultruding a plastics resin material with longitudinally extending mats of glass fibers and longitudinally extending unidirectional fibers to form a base wall integrally connecting upwardly projecting and longitudinally extending tubular ribs each having a generally square cross-sectional configuration. The opposite side surfaces of each rib converge slightly towards the base wall, and longitudinally extending ribs or ears project laterally outwardly from the side surfaces to aid in resisting potential vertical shearing at the concrete and composite panel interfaces. The pultrusion is cut into sections or panels of predetermined lengths, and the top surface of each deck panel is coated with epoxy adhesive and an aggregate of crushed stone to protect the deck section against alkaline attack from concrete and to provide positive bonding to concrete.
The deck panels are positioned or assembled in laterally adjacent overlapping relation and span parallel spaced steel frame members or beams to form a permanent pultruded deck form. A mat or grid of fiber reinforced composite rods are spaced above the deck panels, and vertical steel studs are welded to the steel beams which support the composite deck panels. The studs project upwardly into a concrete layer which is poured onto the deck panels to a predetermined level above the composite reinforcing rods.
Other features and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims.